People tried to call David Budd after he gave out his number on Bodyguard

However, some fans noticed Budd’s digits had already been revealed, in episode five when Richard Madden’s PPO gave out his phone number (07700900431) to Chanel Dyson – the shady former assistant to home secretary Julia Montague (Keeley Hawes).

And turns out eager viewers actually noted it down…

But what happened when they rung? Nothing. That’s because the number is one of the 20,000 fake combinations designated by broadcasting regulator Ofcom for use in TV, radio and film (see the full list here).

The not-in-use combinations include numbers for different areas around the UK as well as those for mobile phones.

That means that however much you want to pass on a message, your favourite TV characters won't answer you back...

Occasionally screen characters accidentally use real numbers, such as the one in Jim Carey film Bruce Almighty. Callers who were expecting to have a chin wag with God were instead connected to a sandwich shop manager from Salford.

In short: if you call a number from a TV show, whether David Budd's or God's, you're not going to reach who you want. Well, they're not going to give out their real numbers on TV, are they?

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Bodyguard concludes on Sunday at 9pm on BBC1